In reply to Hillseeker:
I use an exposure strada and joystick but that's over your budget.
You won't regret buying a good light, but you will regret buying a bad one, and it'll work out more expensive in the long run.
Before the Exposure combo I used to run two lights on my bars, an Cateye Volt 300 and a B&M Ixon Core (they got nicked). The latter is a particularly good road riding light, not too expensive either, puts the light where you need it so doesn't dazzle cars, no flashing/pulsing mode. The pulsing mode on the Cateye volt is excellent too, flashing is difficult to gauge, pulsing is much easier